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ESS fully charging batteries with solar first?

Hello everyone,

We just installed a system with two Multiplus II 2kW 48VDC and Cerbo GX. The system is configured with ESS and every night the batteries are drained to the lowest SOC so the grid supports automatically. That's fine.

Early next day the MPPT controller begins charging the battery bank, and at the same time powering loads. I am wondering if it could be possible that the solar charger takes batteries at a full charge first, and meanwhile the inverters power loads from grid until the batteries reach 100% SOC. I mention this because batteries are not reaching 100% SOC. There is enough PV power to a full recharge but the power is shared at the same time with the loads. The idea is to charge batteries with solar first, without being discharged since early morning and keep them charged to be used at night.

Thank you in advance for your help.

dgmar-ni asked

0 Answers

ESS issues when switching from Inverter/Charger to External Meter Grid Metering

Hi all,

I have a very simple ESS setup which works as expected under the internal grid meeting.

Multiplus II 5000VA with Cerbo GX + 2x Pylontech US3000C

Everything works well although in order to get the Critical Load function to operate with a grid failure, you must enable an External Meter. Fine:

In my case, I have the official Victron Current sensor 100A:50mA with the jack cut off and wired as per the manual. Please see here: (3.5mm jack was deemed unreliable hence a connector block on new models)

I've verified that the external current sensor is operating correctly because it provides sensible values on a known load. Plus same values as if it were working in the internal current sense.

Anyway, as soon as I switch my Multiplus Grid Meeting from Internal (Inverter/Charger) to External Meter.

Any form of charging and discharging from the Pylontechs fails to happen!

(Unit stays in grid passthrough mode)

Any suggestions on what could be my issue?

Many Thanks!

llyr-roberts asked
rata1 edited ·

1 Answer

Adding extra PV system, Multiplus and battery storage, DNO dilemma

Currently have a 3.6kw FIT system installed 10 years ago. I want to add a new Battery storage system with an extra 3kw solar and use a multiplus II(48/5000/75) setup for ESS. Setup so it does not affect the FIT system

Having scoured the forums i decided to approach National grid (western power) to discuss a DNO application. They have initially said " i dont think you can do a self install, please speak to a qualified installer"

My plan was to do all the infrastructure work and an electrician( (not MCS qualified) safety check and make the final connections and sign off the work for building regs.

Any advice how to proceed?


bigone001 asked
rata1 answered ·

2 Answers

Quattro II - Wrong advertising promise or misunderstood ESS with generator?

Hello friends of the blue devices,

is there a false advertising promise from Victron?.

I bought 3 Quattro II, a Cerbo GX and 6x MPPT 150/70 VE.Can. Then I installed 14kWp PV and a 11kWh battery with diyBMS. Everything has been going great for about 2 months - except for the advertising promise with the generator.

Of course I installed the ESS Assistant in all 3 Quattros - there's no other way if you want to use the PV power yourself and want to store excess power in the battery. My 8kVa generator with Honda motor and AVR on each phase is connected to AC In1 as the owner's manual recommends.

Germany with internal NS protection is set as the grid code. LOM activated at AC IN 1+2. The generator is not recognized. LOM disabled at AC IN1 - nothing! Then I found that the generator is set to 52Hz, so I set it to around 50Hz - the generator is recognized after a very long time and serves phase 1+2+3. But no charging of the battery - which is the most important thing for me. After this connection was not stable either, I switched to EXTERNAL NA protection. This keeps the generator stable in the system. However, there is no PowerAssist and no support from the Quattro II inverter.

IF I suddenly switched on 4000W the Quattro II throw the generator out of the system again. I only want to charge the battery with the generator and the other consumers as before with an inverter using MPPT and battery power. So as if the grid is available on AC IN2 and no generator is connected. It works there too. I've tried everything with the generator - minimum SOC set to 100% or always keep the battery charged - all the setting options...nothing. You can only use the generator to operate connected consumers in the house without any support from the QUATTRO II. That sounds somehow different in the advertising. It doesn't say "all this will only work with your generator if you don't install an ESS". Then I should have saved a lot of money and would have bought 3 Multiplus II and 3 additional power supplies with a total of 7kW to charge the battery with the 3-phase generator.

Is there someone among you who knows more about this and can help me?


mrfrodo asked
djsmiley commented ·

12 Answers

ESS mislabeled state?

Hello, maybe it's just a misprint in the web or something, but it states "external control" in both modes, is this OK?

1x Victron Quattro 15000VA

5x Weco 5K3 Battery

1x Cerbo




Maybe it refers to the fact that the inverter is controlled by the Cerbo, but is a little confusing.


Mario Navarro asked
Mario Navarro commented ·

1 Answer

Multiplus 1 48/3000 : interdire la charge depuis le GRID (EDF)

Bonjour à tous

Je débute avec mon Multiplus.

Multiplus 1 + ET112 + enphase sur ACIN + batterie:

Tout fonctionne sauf que de temps en temps, le multiplus charge la batterie depuis le réseau EDF et décharge juste après.

Savez vous comment interdire la charge depuis le réseau ?


moriss asked
Thierry Cortassa (Victron Energy Staff) answered ·

2 Answers

Victron ESS with Solaredge zero feed in?


There is a system:

3 х MultiPlus-II 48/5000/70-48, PV Inverter Solaredge SE7K-RW0TEBNN4 PositionAC output

All settings have been made as per the document:

Cerbo GX has all settings and restrictions set

As a result, there is generation into the grid


Question: How do stop generation into the grid?

Thanks to everybody willing to help!

vkaraim asked

0 Answers

SoC why is it so flaky?

I have two installations both ESS grid-parallel battery systems both primarily time-shifting off-peak electricity to peak times. Each using multiplus II 48/5000/70 units.

2p16S configuration brand new EVE 230Ah LiFePO4 cells with Daly BMS 250 amp.

However, despite the nameplate capacity being 48V 460Ah for each pack, the actual performance varies considerably with temperature for example. As such I might get 300Ah before the SoC shows as low (I am using 25% SoC as ESS low limit) or I might get 350Ah.

I understand that voltage, on paper, is a more accurate measure of charge, than counting charge in and out (Ah) but under load, it is unreliable as it drops. So we use SoC whilst under load. However, it doesn't seem to be very intuitive or clever.

How is the battery pack in my MG5 LR EV managing itself without what I am having to do - the constant tweaking of the capacity in VEconfigure or the ESS stop on SoC level.

I want to set the thing up and then forget about it.

Also, can someone explain what the adaptive charging in veconfigure is all about?

djdemond asked
Al answered ·

3 Answers

Electric car as homebattery

Has anyone experiences with using an electric-car as home battery. Although not all cars are suitable for a bi-directional connections, i am curious to know if their is already some experiences with this. In addition how to connect it in combination with a 3-phase Victron Multi plus II setup?

Kees-Jan asked
geoffrey-schmitz edited ·

4 Answers

3phase Mp2 48/5000/30 with Pylontech 5000 - ESS trouble


I use 3x MP2 48/5000/70 in a three phase system with 2x Pylontech U5000. It is all installed fix at home, no mobile solution. As long as I do not try to configure a ES, it is working like a charm. It changes the batteries and discharges them in case of switching off AC input.

Even configuring an ESS seems to work from VEConfigure for each single of the MP2. But then in the Remote-Console there are no ESS-Assistants available, strange enough.


The battery itself is communicating to the Cerbo, and I got the impression that this is doing a kind "whipping out" my ESS settings again, like overwriting my settings done in VEConfigure. Not sure, but it looks like.


All my firmware is upgraded to the latest version:


Does anyone please have an idea where the problem with the ESS might be coming from?

As I am still waiting to the delivery of my energy meter (EM24), is it possible that this is a prerequisite? If so, why this ist not mentioned by the software? And if not - how to fix my problem, please?

kind regards

fonsel asked
fonsel edited ·

1 Answer

Multiplus II 48/3000/35-32 and CEC Approval (Australia) - ESS Not Allowed

Multiplus II 48/3000/35-32 Inverter is CEC listed as approved as Stand Alone Inverter With Generator Input Battery Only. This means my local electricity distributor will not allow it to be grid connected in an ESS configuration.

The approval certificate is Certificate SAA181339.pdf.

That certificate shows compliance with:

IEC 62109-1 Ed 1.0,
IEC 62109-2 Ed 1.0,
AS 62477.1:2016 and
AS/NZS 4777.2:2020 Inc A1

The CEC document CEC-inverter_listing_categories_2021.pdf (p2) indicates the Multiplus II 48/3000/35-32 Inverter meets the requirements as a Multiple Mode Inverter and hence approved as a Grid Interactive inverter.

As I have just acquired 2 Multiplus II 48/3000/35-32 in Jan 2022 for use in a parallel ESS system with Fronius inverter on AC1 Out, this has become an issue.

Is there any reason the Multiplus II 48/3000/35-32 Inverter is not listed as a Multiple Mode Inverter?

bipedalprimate asked
bipedalprimate edited ·

1 Answer

ev charger only grid use

Hello Victron Community,

I am new to the forum and would like to build my own ess system from victron with a multiplus 2 and pylontech batteries.

my question is i have an ev from my employer that i would like it to not use the batteries. I get paid the kw/h price immediately and the car consumes 60kw per day. I can't put that much solar panel on my house ;). therefore want to use the ess system only for my own consumption. is it possible to use a 2nd energy meter for only the charging station, which calculates the difference so that charging only takes place via the grid.

I would like to hear what you think about it, I can't really find a solution on the internet and whether it is possible via ess from victron

Kind regards

Menno van Ninhuijs from the Netherlands

p.s. charging station is an Alfen eve with load balancing via P1 port on the grid meter

mvanninhuys asked
stefmari answered ·

6 Answers

Check: the difference between AC-out-2 and AC-in

Hi, I am just starting out with Victron, and want to ensure that I have understood the Multiplus II's AC logic correctly (specifically, in ESS mode).

It's clear enough from documentation that AC-out-1 is protected by the battery and always live (provided no fault condition), and AC-out-2 is only energised when power is present on AC-in. I also gather from Appendix B of the manual that the transfer relay is normally closed when AC-in is live and that, to the MP2, there is no difference between loads on AC-out-1 and AC-out-2.

Appendix B also shows that current is measured at two points: directly at the inverter output, and at AC-in. Between them, so far as I can work out, they allow the MP2 to detect and prevent overload conditions on the inverter, to implement PowerControl, and anyway to limit current drawn on AC-in by the charger according to something less than the breaker supplying AC-in. PowerAssist is implemented by means of an ET112.

That all seems fairly straight forward. (Have I missed anything?)

Does it matter if there are loads, possibly quite large loads (oven, 3kW kettle, 2kW AC etc) between the ET112 and AC-in, or do they have to be connected to AC-out-2? In an ESS situation, do I ever need to use AC-out-2 for any purpose?

It seems not, so far as I understand it. Their current draw will still be seen via the ET112 and, because AC-in, AC-out-1 and AC-out-2 are all directly coupled via relays, even loads upstream of the inverter will benefit from PowerAssist (so long as grid power is present, of course). This is also why PV inverters can be installed in parallel with any of the AC ports on the MP2: everything is galvanically connected when grid power is present.

The one difference I can see is that PowerControl likely won't work if I do not have my non-essential loads wired into AC-out-2, because it probably does not look at the ET112 for the current draw of upstream loads. But I also don't see how that matters in a situation where it is impossible, or else very unlikely that even with the MP2's charger drawing as much current as it can, that total load could exceed cutout/service fuse rating (or that of respective RCBOs').

In which case, when I install this thing, I have a bit more freedom as to where to install the MP2. I need only divide my consumer unit into two, install two runs of 10mm² (good enough for 50A) from the consumer unit to AC-in and back from AC-out-1 to the consumer unit to power protected half.

Have I understood all this correctly? Thanks.

strix asked
strix commented ·

1 Answer

ESS minimum SOC top up with scheduled charging

Hi folks,

running a 3-phase 5kVA MP-II system here, AC-coupled PV on AC_out, running 4 batteries with internal BMS and relying on smartshunt for voltage/SOC here, hence no DVCC. Float ist set to 55,4V, absorption to 57V in the multis.

The scenario in this case is, that the grid is almost always there, so the purpose is maximisation of self-consumption.

Therefore a minimum SOC of just 20% has been set, which "unfortunately" is being undermined by a few DC loads connected to the battery - my first understanding of the min SOC was wrong here, I somehow expected a "keep charged at 20%" feature.

So to battle this I opted to charge n schedule once per day to reach the 20% again for emergency purposes. I do successfully enter the "scheduled charging" state, so I don't have the time problem many others seem to have. I just can't seen any rise in voltage or current. Where is my problem? :)


Voltage keeps dropping...


Any ideas? :)

Just in case the relevant settings:





martin-henning asked
guy-cashmore commented ·

1 Answer

Multiplus II 5000 Application and Questions


I'm planning and understanding what I need from a high level design before I start talking to qualified installers in my area.

I'm in Cape Town/South Africa and we have load shedding daily and outages between 2-8 hours a day. So I'm looking at a MultiPlus II 5000 GX, MPPT RS 450/200, 1 or more 51.2V 100Ah LiFeP04 batteries with onboard BMS (Victron compatible) and ±15 x 545W PV Panels totaling ±8kW max output.

Working from home I want to design/split my load circuits into 3 categories, Critical Loads (Office, IT equipment, Fibre, WiFi and networking with average 1.4A max 2.5A), Essential Loads (Lights, house power points, small appliances, fridges and freezers) and Non-Essential Loads (Pool pump, geysers, heat pumps, aircons).

My idea is that I have my Critical loads on ACOut1, Essential Loads on ACOut2 and Non-Essential on the same circuit as ACIn.


  1. Can the ACOut2 relay be controlled to switch off if no grid, no solar and battery SOC is say less than 30%? That way I can keep at least my Critical loads running off battery a little longer.
  2. Is there a benefit of having a MultiPlus II + Cerbo vs Multiplus II GX?
  3. In this configuration, can excess solar be used to supply the Non-Essential loads to save on grid or alternatively feed-in to grid (with the correct meters and approval)?
  4. The MPPT RS spec on its DC Output charging power is confusing. 4kW per tracker but its max total is 11.5kW. Can someone explain this? I assumed the 450/100 will be to small for my application?
  5. On the City of Cape Town approved inverters dated 2023-01-06 (link below), the MultiPlus II 5000 is listed but not the GX model. Compared to the MultiPlus II 3000 GX where both models are listed. Is the 5000 GX in the process of being approved or can you consider the 5000 and 5000 GX to be the same inverter model with just the addition of the GX functions?

Thanks in advance

City of Cape Town approved inverters 2023-01-06

Joos Louw asked
Joos Louw commented ·

2 Answers

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